Segment Information - MEC (Details) $ in Millions	3 Months Ended							9 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) OperatingSegments TheNumberOfReportableSegments	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | OperatingSegments									8
Revenues									$ 17,880	$ 17,326	$ 12,635
Operating income (loss)									4,328	4,046	2,835
Interest expense									1,904	1,711	1,222
Income tax (benefit) expense									450	589	130
Payments to Acquire Property, Plant, and Equipment									5,875	6,555	4,307
Assets	$ 83,618				$ 81,816				$ 83,618	81,816	69,591
MidAmerican Energy Company [Member]
Segment Reporting Information [Line Items]
Number of Reportable Segments | TheNumberOfReportableSegments									3
Electric Domestic Regulated Revenue									$ 1,837	1,817	1,762
Gas Domestic Regulated Revenue									661	996	824
Other Revenue, Net									909	927	817
Revenues	748	$ 920	$ 793	$ 946	884	$ 769	$ 1,225	$ 862	3,407	3,740	3,403
Utilities Operating Expense, Depreciation and Amortization									407	351	403
Operating income (loss)	33	$ 210	$ 122	$ 106	58	$ 51	$ 153	$ 160	471	422	356
Interest expense									183	174	151
Income tax (benefit) expense									(141)	(104)	(103)
Net Income (Loss) Available to Common Stockholders, Basic									462	417	349
Payments to Acquire Property, Plant, and Equipment									1,446	1,526	1,026
Assets	14,385				13,234				14,385	13,234	11,848
MidAmerican Energy Company [Member] | Regulated Electric [Member]
Segment Reporting Information [Line Items]
Electric Domestic Regulated Revenue									1,837	1,817	1,762
Utilities Operating Expense, Depreciation and Amortization									366	312	366
Operating income (loss)									385	319	255
Interest expense									166	157	136
Income tax (benefit) expense									(163)	(138)	(136)
Net Income (Loss) Available to Common Stockholders, Basic									413	361	292
Payments to Acquire Property, Plant, and Equipment									1,365	1,429	945
Assets	12,970				11,850				12,970	11,850	10,521
MidAmerican Energy Company [Member] | Regulated Gas [Member]
Segment Reporting Information [Line Items]
Gas Domestic Regulated Revenue									661	996	824
Utilities Operating Expense, Depreciation and Amortization									41	39	37
Operating income (loss)									64	75	74
Interest expense									17	17	15
Income tax (benefit) expense									16	22	23
Net Income (Loss) Available to Common Stockholders, Basic									33	40	41
Payments to Acquire Property, Plant, and Equipment									81	97	81
Assets	1,251				1,217				1,251	1,217	1,196
MidAmerican Energy Company [Member] | Nonregulated Energy [Member]
Segment Reporting Information [Line Items]
Other Revenue, Net									909	927	817
Operating income (loss)									22	28	27
Income tax (benefit) expense									6	12	10
Net Income (Loss) Available to Common Stockholders, Basic									16	16	16
Assets	$ 164				$ 167				$ 164	$ 167	$ 131